Expandable spinal implants

ABSTRACT

A spinal implant has a proximal region and a distal region, and includes an upper body and a lower body each having inner surfaces disposed in opposed relation relative to each other. A proximal adjustment assembly is disposed between the upper and lower bodies at the proximal region of the spinal implant and is adjustably coupled to the upper and lower bodies, and a distal adjustment assembly is disposed between the upper and lower bodies at the distal region of the spinal implant and is adjustably coupled to the upper and lower bodies. The proximal and distal adjustment assemblies are independently movable with respect to each other to change a vertical height of at least one of the proximal region or the distal region of the spinal implant.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of, and priority to, U.S.Provisional Patent Application Ser. No. 62/090,429, which was filed onDec. 11, 2014, U.S. Provisional Patent Application Ser. No. 62/158,470,which was filed on May 7, 2015, and U.S. Provisional Patent ApplicationSer. No. 62/206,779, which was filed on Aug. 18, 2015, the entirecontents of each of which are hereby incorporated herein by reference.

TECHNICAL FIELD

The present disclosure relates generally to orthopedic surgical devices,and more particularly, to expandable spinal implants configured forpositioning within an intervertebral space, associated instrumentations,and methods of using the same.

BACKGROUND

The spinal column is a complex system of bones and connective tissuesthat provide support for the human body and protection for the spinalcord and nerves. The adult spine includes an upper portion and a lowerportion. The upper portion contains twenty-four discrete bones, whichare subdivided into three areas including seven cervical vertebrae,twelve thoracic vertebrae, and five lumbar vertebrae. The lower portionincludes the sacral and coccygeal bones. The cylindrical shaped bones,called vertebral bodies, progressively increase in size from the upperportion downwards to the lower portion.

An intervertebral disc along with two posterior facet joints cushion anddampen the various translational and rotational forces exerted upon thespinal column. The intervertebral disc is a spacer located between twovertebral bodies. The facets provide stability to the posterior portionof adjacent vertebrae. The spinal cord is housed in the canal of thevertebral bodies. It is protected posteriorly by the lamina. The laminais a curved surface with three main protrusions. Two transverseprocesses extend laterally from the lamina, while the spinous processextends caudally and posteriorly. The vertebral bodies and lamina areconnected by a bone bridge called the pedicle.

The spine is a flexible structure capable of a large range of motion.There are various disorders, diseases, and types of injury, whichrestrict the range of motion of the spine or interfere with importantelements of the nervous system. The problems include, but are notlimited to, scoliosis, kyphosis, excessive lordosis, spondylolisthesis,slipped or ruptured disc, degenerative disc disease, vertebral bodyfracture, and tumors. Persons suffering from any of the above conditionstypically experience extreme and/or debilitating pain, and often timesdiminished nerve function. These conditions and their treatments can befurther complicated if the patient is suffering from osteoporosis, orbone tissue thinning and loss of bone density.

Spinal discs between the endplates of adjacent vertebrae in a spinalcolumn of the human body provide critical support. However, due toinjury, degradation, disease or the like, these discs can rupture,degenerate, and/or protrude to such a degree that the intervertebralspace between adjacent vertebrae collapses as the disc loses at least apart of its support function. This can cause impingement of the nerveroots and severe pain.

In some cases, surgical correction may be required. Some surgicalcorrections include the removal of the natural spinal disc from betweenthe adjacent vertebrae. In order to preserve the intervertebral discspace for proper spinal column function, an interbody spacer can beinserted between the adjacent vertebrae.

Typically, a prosthetic implant is inserted between the adjacentvertebrae and may include pathways that permit bone growth between theadjacent vertebrae until they are fused together. However, there existsa possibility that conventional prosthetic implants may be dislodged ormoved from their desired implantation location due to movement by thepatient before sufficient bone growth or fusion has occurred. Due to theconcave nature of the vertebral body endplates, it can be challenging toobtain enough contact between the implant and the endplates to createbone growth. Additionally, achieving the desired lordosis can bedifficult given the limitation of typical prosthetic implants once theyare implanted.

Therefore, a need exists for a spinal implant that provides maximumcontact with the vertebral body endplates, matches the desired amount oflordosis, allows for bone growth between adjacent vertebrae, maintainsthe space between adjacent vertebrae during bone ingrowth, and/orresists dislocation from its implantation site.

SUMMARY

In accordance with an aspect of the present disclosure, a spinal implanthaving a proximal region and a distal region includes an upper body, alower body, a proximal adjustment assembly, and a distal adjustmentassembly. Each of the upper and lower bodies includes an outer surfaceand an inner surface, and the inner surfaces of the upper and lowerbodies are disposed in opposed relation relative to each other. Theproximal adjustment assembly is disposed between the upper and lowerbodies at the proximal region of the spinal implant and is adjustablycoupled to the upper and lower bodies. The distal adjustment assembly isdisposed between the upper and lower bodies at the distal region of thespinal implant and is adjustably coupled to the upper and lower bodies.The proximal and distal adjustment assemblies are independently movableto change a vertical height of at least one of the proximal region orthe distal region of the spinal implant.

In embodiments, the proximal adjustment assembly includes a rampslidably movable along the proximal region of the spinal implant tochange the vertical height of the proximal region of the spinal implant.The ramp may include upper and lower rails that taper from a proximalend towards a distal end of the ramp. The distal end of the ramp may bedisposed between the upper and lower bodies, and the ramp may beslidable between the upper and lower bodies to increase the verticalheight of the proximal region of the spinal implant. Each of the upperand lower rails may include an inner surface, each of the inner surfacesof the upper and lower rails may include a plurality of groovesextending along a length thereof. The proximal adjustment assembly mayfurther include a first set of pins coupled to the inner surface of theupper body and positioned against the inner surface of the upper rails,and a second set of pins coupled to the inner surface of the lower bodyand positioned against the inner surface of the lower rails. The firstand second sets of pins may ride along the plurality of grooves of theupper and lower rails during movement of the ramp.

In embodiments, the distal adjustment assembly includes a pivot linkageassembly including an upper pivot linkage pivotably connected to theinner surface of the upper body, and a lower pivot linkage pivotableconnected to the inner surface of the lower body. The upper and lowerpivot linkages are pivotably connected to each other and movable withrespect to each other to change the vertical height of the distal regionof the spinal implant.

The distal adjustment assembly may include a curved plate having acurved distal surface movable into and out of contact with the pivotlinkage assembly to effect movement of the upper and lower pivotlinkages with respect to each other. The distal adjustment assembly mayinclude a threaded post including a distal end retained against aproximal surface of the curved plate, wherein axial movement of thethreaded post moves the curved plate. The distal adjustment assembly mayinclude a bracket including a threaded opening and a pair of legsextending distally therefrom. The threaded post may be threadinglyengaged with the threaded opening of the bracket and axially movabletherethrough. The curved plate may be slidably disposed between the pairof legs of the bracket, and the upper and lower pivot linkages may bepivotable connected to each other by a pin extending through the upperand lower pivot linkages and a distal end of the pair of legs of thebracket.

The distal adjustment assembly may include a threaded post including adistal end movable into and out of contact with the pivot linkageassembly to effect movement of the upper and lower pivot linkages withrespect to each other. The distal adjustment assembly may include anexpander including a body portion defining a cavity therein and a distalend including a double ramped inner surface. The pivot linkage assemblymay extend through the cavity of the expander such that pivot linkagescontact the double ramped inner surface of the expander when moved bythe threaded post. The expander may include a shaft extending proximallyfrom the body portion. The shaft may include a threaded opening definedtherein, and the threaded post may be threadingly engaged with thethreaded opening of the shaft and axially movable therethrough into thecavity of the expander.

In embodiments, each of the inner surfaces of the upper and lower bodiesincludes a pair of proximal fins defining angled slots therethrough, andthe proximal adjustment assembly includes a linkage body and a first setof pins. The linkage body includes a pair of arms extending alonglateral sides thereof, and each arm of the pair of arms includes adistal hole. The first set of pins is disposed within the distal holesof the linkage body and into the angled slots of the upper and lowerbodies. Movement of the linkage body causes the first set of pins totranslate within the angled slots to change the vertical height of theproximal region of the spinal implant.

The proximal adjustment assembly may include a flange nut having athreaded opening defined therethrough that is threadingly engaged withthe threaded post of the distal adjustment assembly. The linkage bodymay include a recess in which a distal flange of the flange nut isdisposed, such that axial movement of the flange nut along the threadedpost effects movement of the linkage body. The pair of proximal fins ofthe upper and lower bodies may define vertical slots therethrough. Theproximal adjustment assembly may include a coupler that includes a pairof nubs extending from lateral sides thereof that is slidably disposedwithin the vertical slots of the upper and lower bodies.

In embodiments, the side surfaces of the upper and lower bodies mayinclude angled slots defined therethrough, and the proximal adjustmentassembly may include a bracket assembly including a plurality of nubsslidably disposed within the angled slots of the upper and lower bodies,such that movement of the bracket assembly causes the plurality of nubsto translate within the angled slots to change the vertical height ofthe proximal region of the spinal implant.

The proximal adjustment assembly may include a nut having a threadedopening defined therethrough that is threadingly engaged with thethreaded post of the distal adjustment assembly, such that axialmovement of the nut along the threaded post effects movement of thebracket assembly.

At least one of the outer surfaces of the upper and lower bodies mayinclude a wing portion that is movable from a retracted position inwhich the wing portion is aligned with the outer surface of the upperbody or the lower body, and a deployed position in which the wingportion is rotated at an angle relative to the outer surface of theupper body or the lower body. At least one of the outer surfaces of theupper body or the lower body may include a plurality of retainingfeatures.

In accordance with another aspect of the present disclosure, a method ofspacing vertebral bodies includes: implanting a spinal implant into adisc space defined between first and second endplates of respectivefirst and second vertebral bodies such that an upper body of the spinalimplant is adjacent the first end plate and a lower body of the spinalimplant, disposed in opposed relation relative to the upper body, isadjacent the second end plate, the spinal implant including proximal anddistal adjustment assemblies disposed between the upper and lowerbodies, the proximal and distal adjustment assemblies independently andadjustably coupled to proximal and distal regions, respectively, of thespinal implant; and adjusting a vertical height of at least one of theproximal region or the distal region of the spinal implant via one ofthe proximal or distal adjustment assemblies such that at least one ofthe outer surfaces of the upper or lower bodies of the spinal implantmatches an anatomical shape of the first or second endplates of thefirst or second vertebral bodies.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are incorporated in and constitute apart of this specification, illustrate embodiments of the disclosureand, together with a general description of the disclosure given above,and the detailed description of the embodiments given below, serve toexplain the principles of the disclosure, wherein:

FIG. 1 is a perspective view of a spinal implant in accordance with anembodiment of the present disclosure;

FIG. 2 is an exploded view of the spinal implant of FIG. 1;

FIGS. 3A and 3B are perspective views of a bracket of the spinal implantof FIGS. 1 and 2;

FIG. 3C-3E are side, end, and cross-sectional views, respectively, ofthe bracket of FIGS. 3A and 3B;

FIGS. 4A and 4B are perspective views of the spinal implant of FIG. 1,in a collapsed position;

FIG. 4C-4E are side, end, and cross-sectional views, respectively, ofthe spinal implant of FIGS. 4A and 4B;

FIGS. 5A and 5B are end and side views, respectively, of the spinalimplant of FIG. 1, with a proximal region of the spinal implant in apartially expanded position;

FIGS. 6A and 6B are perspective views of the spinal implant of FIG. 1,with a proximal region of the spinal implant in a fully expandedposition;

FIG. 6C is an end view of the spinal implant of FIGS. 6A and 6B;

FIGS. 6D and 6E are cross-sectional views of the spinal implant of FIGS.6A-6C, taken along lines 6D-6D and 6E-6E, respectively, of FIG. 6C;

FIGS. 7A and 7B are end and side views, respectively, of the spinalimplant of FIG. 1, with proximal and distal regions of the spinalimplant each in a partially expanded position;

FIGS. 8A and 8B are end and side views, respectively, of the spinalimplant of FIG. 1, with a proximal region of the spinal implant in apartially expanded position and a distal region of the spinal implant ina fully expanded position;

FIGS. 9A and 9B are perspective views of the spinal implant of FIG. 1,with a proximal region of the spinal implant in a fully expandedposition and a distal region of the spinal implant in a partiallyexpanded position;

FIGS. 10A and 10B are perspective views of the spinal implant of FIG. 1,with proximal and distal regions of the spinal implant each in a fullyexpanded position;

FIG. 10C is a side view of the spinal implant of FIGS. 10A and 10B:

FIG. 10D is a cross-sectional view of the spinal implant of FIGS.10A-10C, taken along line 10D-10D of FIG. 10C;

FIG. 10E is a close-up view of the area of detail indicated in FIG. 10D;

FIGS. 11A-11E are perspective views of a system including the spinalimplant of FIG. 1 and an insertion instrument in accordance with anembodiment of the present disclosure;

FIG. 11F is a close-up view of the area of detail indicated in FIG. 11E;

FIG. 11G is a perspective view of the area of detail of the system ofFIG. 11F;

FIGS. 11H and 11I are perspective views of the system of FIGS. 11A-11E;

FIG. 11J is a close-up view of the area of detail indicated in FIG. 11I;

FIGS. 12A and 12B are perspective views of a spinal implant inaccordance with another embodiment of the present disclosure;

FIG. 13 is an exploded view of the spinal implant of FIGS. 12A and 12B;

FIGS. 14A-14C are side, top, and cross-sectional views, respectively, ofthe spinal implant of FIGS. 12A-12B, in a collapsed position;

FIG. 15 is a cross-sectional view of the spinal implant of FIGS.12A-12B, with a distal region of the spinal implant in a partiallyexpanded position;

FIG. 16 is a side view of the spinal implant of FIGS. 12A-12B, with adistal region of the spinal implant in a fully expanded position;

FIGS. 17A and 17B are side and cross-sectional views, respectively, ofthe spinal implant of FIGS. 12A-12B, with proximal and distal regions ofthe spinal implant each in a fully expanded position;

FIGS. 18A-18E are perspective views of a system including the spinalimplant of FIGS. 12A-12B and an insertion instrument in accordance withan embodiment of the present disclosure;

FIG. 19 is a perspective view of a spinal implant in accordance withanother embodiment of the present disclosure, with wing portions of thespinal implant in a retracted position;

FIG. 20 is a perspective view of the spinal implant of FIG. 19, with thewing portions of the spinal implant in a deployed position;

FIG. 21 is an exploded view of the spinal implant of FIG. 19;

FIGS. 22A and 22B are perspective views of an upper body and a lowerbody, respectively, of the spinal implant of FIG. 19, with partsseparated;

FIGS. 23A and 23B are end and side views, respectively, of the spinalimplant of FIG. 19, in a collapsed position;

FIGS. 24A and 24B are end and side views, respectively, of the spinalimplant of FIGS. 23A and 23B, with the wing portions in a deployedposition;

FIGS. 25A-25C are end, side, and cut-away views, respectively, of thespinal implant of FIG. 19, with a distal region of the spinal implant ina fully expanded position;

FIGS. 26A-26C are end, side, and cross-sectional views, respectively, ofthe spinal implant of FIG. 19, with a proximal region of the spinalimplant in a fully expanded position and a distal region of the spinalimplant in a partially expanded position; and

FIGS. 27A-27C are end, side, and perspective views, respectively, of thespinal implant of FIG. 19, with proximal and distal regions of thespinal implant each in a fully expanded position.

DETAILED DESCRIPTION

Embodiments of the present disclosure are now described in detail withreference to the drawings in which like reference numerals designateidentical or corresponding elements in each of the several views. Theterm “clinician” refers to a doctor (e.g., a surgeon), a nurse, or anyother care provider, and may include support personnel. Throughout thisdescription, the term “proximal” refers to a portion of a device orcomponent thereof that is closer to a clinician, and the term “distal”refers to the portion of the device or component thereof that is fartherfrom the clinician.

Referring now to the drawings, FIG. 1 illustrates an expandable spinalimplant or a spinal implant 100 in accordance with an embodiment of thepresent disclosure. Spinal implant 100 has a proximal region 100 a and adistal region 100 b extending along a longitudinal axis “X.” The spinalimplant 100 includes an upper body 110 and a lower body 130 disposed inopposed relation relative to each other and coupled together by aproximal adjustment assembly 150 and a distal adjustment assembly 170.The proximal and distal adjustment assemblies 150, 170 are independentlymovable to allow for adjustment in the distance between the upper andlower bodies 110, 130 of the proximal and distal regions 100 a, 100 b ofthe spinal implant 100 along a transverse axis “Y.” Accordingly, thespinal implant 100 is movable between a collapsed position and a fullyexpanded position, and includes a number of partially expandedpositions, as described in further detail below.

Turning now to FIG. 2, the upper body 110 of the spinal implant 100includes an elongated substantially planar portion 112 having a proximalend 112 a and a distal end 112 b, and a curved portion 114 disposeddistally of the distal end 112 b of the planar portion 112. An outersurface 116 of the planar portion 112 includes a plurality of retainingfeatures 116 a configured to frictionally engage an adjacent surface ofa vertebral body (i.e., a vertebral endplate) to maintain the positionof the spinal implant 100 relative to the vertebral body and to inhibitthe spinal implant 100 from backing out of the intervertebral space asthe plurality of retaining features 116 may bite into the vertebralendplate. The plurality of retaining features may be ridges,protrusions, bumps, teeth, or any other texturized structure, as iswithin the purview of those skilled in the art.

An inner surface 118 of the upper body 110 includes two pairs ofproximal posts 120 extending from the proximal end 112 a of the planarportion 112. Each proximal post 120 includes a through hole 120 adefined therethrough that is aligned with the through holes 120 a of theother proximal posts 120. The inner surface 118 of the upper body 110also includes a pair of distal posts 122 extending from the distal end112 b of the planar portion 112, proximate to the curved portion 114.Each distal post 122 include a through hole 122 a defined therethrough.It should be understood that the proximal and distal posts 122 that arenot shown are identical to the proximal and distal posts 122 shown, andsimilar to the proximal and distal posts 140 and 142 of the lower body130.

The lower body 130 includes an elongated substantially planar portion132 having a proximal end 132 a and a distal end 132 b, and a curvedportion 134 disposed distally of the distal end 132 b of the planarportion 132. The planar portion 132 includes an outer surface 136 havinga plurality of retaining features (not shown) disposed thereon that areconfigured to frictionally engage an adjacent surface of a vertebralbody as discussed above with regard to the plurality of retainingfeatures 116 a of the upper body 110. An inner surface 138 of the lowerbody 130 includes two pairs of proximal posts 140 extending from theproximal end 132 a of the planar portion 132. Each proximal post 140includes a through hole 140 a defined therethrough that is aligned withthe through holes 140 a of the other proximal posts 140. The innersurface 138 of the lower body 130 also includes a pair of distal posts142 extending from the distal end 132 b of the planar portion 132,proximate to the curved portion 134. Each distal post 142 includes athrough hole 142 a defined therethrough.

The proximal adjustment assembly 150 includes a ramp 152 having aproximal wall 154 at a proximal end 152 a of the ramp 152. The proximalwall 154 includes a central opening 154 a (see e.g., FIG. 4A) definedtherethrough. A pair of upper rails 156 and a pair of lower rails 158extend distally from the proximal wall 154 towards a distal end 152 b ofthe ramp 152. The upper and lower rails 156, 158 are inclined and taperfrom the proximal end 152 a to the distal end 152 b of the ramp 152 suchthat when viewed from the side, the ramp 132 defines a wedge shape. Thedistal end 152 b of the ramp 152 includes a pair of opposed guides 160that are configured to engage arms 186 of a bracket 174 of the distaladjustment assembly 170, and be guided therealong.

Each upper rail 156 includes an outer surface 162 and an inner surface164, and each lower rail 158 includes an outer surface 166 and an innersurface 168. The outer surfaces 162, 166 of the upper and lower rails156, 158 face the inner surfaces 118, 138 of the upper and lower bodies110, 130 and are configured to slide relative thereto. The innersurfaces 164, 168 of the upper and lower rails 156, 158 are disposed inopposed and tapering spaced relation relative to each other. A pluralityof grooves 169 extend along each of the inner surfaces 164, 168 of theupper and lower rails 156, 158. The plurality of grooves 169 may be aplurality of recesses, indentations, depressions, or the like forproviding the inner surfaces 164, 168 of the upper and lower rails 156,158 with an undulating surface.

Each upper rail 156 is received between a pair of the proximal posts 120of the upper body 110 such that the through holes 120 a of the proximalposts 120 are aligned with a groove 169 of the plurality of grooves 169extending along the inner surface 164 of the upper rails 158. A firstset of pins 151 respectively extends through and frictionally engages apair of the proximal posts 120 and one groove 169 of the upper rails 158to couple the upper body 110 to the ramp 152. Similarly, each lower rail158 is received between a pair of the distal posts 140 of the lower body130 such that through holes 140 a of the distal posts 140 are alignedwith a groove 169 of the plurality of grooves 169 extending along theinner surface 168 of the lower rail 158. A second set of pins 153respectively extends through and frictionally engages a pair of thedistal posts 140 and the groove 169 of the lower rails 158 to couple thelower body 130 to the ramp 152.

The first and second set of pins 151, 153 are configured to ride alongthe plurality of grooves 169 of respective upper and lower rails 156,158 of the ramp 152 as the ramp 152 is moved proximally and/or distallywith respect to the upper and lower bodies 110, 130. Accordingly, theramp 152 is mechanically coupled to the upper and lower bodies 110, 130and movable into and out of a space disposed between the upper and lowerbodies 110, 130 to change the distance between the upper and lowerbodies 110 and 130, and thus, the angular position and the verticalheight of the spinal implant 100 about the proximal region 100 a of thespinal implant 100.

The distal adjustment assembly 170 includes a threaded post or screw172, a bracket 174, a curved plate 176, and a pivot linkage assembly 177including an upper pivot linkage 178 and a lower pivot linkage 180. Thethreaded post 172 includes an elongated threaded body 172 a having aproximal end 172 b configured to mate with a driver 15 of an insertioninstrument 10 (see e.g., FIG. 11H) and a flanged distal end 172 ccoupled to the curved plate 176. The proximal end 172 b of the threadedpost 172 may have a shape, such as a hex shape (not shown) for matingwith the insertion instrument.

As shown in FIGS. 3A-3E, in conjunction with FIG. 2, the bracket 174includes a base plate 182 defining a threaded opening 182 atherethrough, and a boss 184 extending proximally from the base plate182 and having a threaded opening 184 a that is coterminous with thethreaded opening 182 a of the base plate 182. The threaded openings 182a and 184 a of the base plate 182 and the boss 184 are configured tothreadingly engage the threaded post 172 such that rotation of thethreaded post 172 results in axial movement of the threaded post 172through the bracket 174. The boss 184 includes a partially flangedproximal end 184 b for connection with an insertion instrument 10 (seee.g., FIG. 11A). The bracket 174 also includes a pair of arms 186extending proximally from the base plate 182 that is configured to guidethe ramp 152, and a pair of legs 188 extending distally from the baseplate 182. The pair of legs 188 includes opposed longitudinal slots 188a and opposed holes 188 b. The opposed holes 188 b are disposed distallyof the longitudinal slots 188 a.

Referring again to FIG. 2, the curved plate 176 includes a curved distalsurface 176 a and a proximal surface 176 b having a cavity 176 c definedtherein (FIG. 10E) that is aligned with and configured to receive andretain the flanged distal end 172 c of the threaded post 172 therein viaa pin 171. A pair of nubs 190 extends laterally from sides of the curvedplate 176 and is disposed, and longitudinally movable, within thelongitudinal slots 188 a of the legs 188 of the bracket 174.

The pivot linkage assembly 177 includes an upper pivot linkage 178having an upper hole 178 a and a lower hole 178 b, and a lower pivotlinkage 180 having a pair of upper holes 180 a and a lower hole 180 b.The upper hole 178 a of the upper pivot linkage 178 is aligned with thethrough holes 122 a defined in the distal posts 122 of the upper body110, and a pin 155 is inserted therethrough for pivotably connecting theupper pivot linkage 178 with the upper body 110. The lower hole 180 b ofthe lower pivot linkage 180 is aligned with the through holes 142 adefined in the distal posts 142 of the lower body 130, and a pair ofpins 157 are inserted therethrough for pivotably connecting the lowerpivot linkage 180 with the lower body 130. The lower hole 178 b of theupper pivot linkage 178 and the upper holes 180 a of the lower pivotlinkage 180 are aligned with the holes 188 b in the legs 188 of thebracket 174, and a pin 159 is disposed therethrough for pivotablysecuring the upper and lower bodies 110 and 130 to the bracket 174 viathe upper and lower pivot linkages 178, 180.

Accordingly, the upper and lower pivot linkages 178, 180 are coupled tothe upper and lower bodies 110, 130, and are pivotable relative to eachother about the pin 159 to change the distance between the upper andlower bodies 110, 130, and thus, the angular position and verticalheight of the spinal implant 100 about the distal region 100 b of thespinal implant 100. Thus, the proximal and distal regions 100 a and 100b of the spinal implant 100 are independently movable with respect toeach other via the proximal and distal adjustment assemblies 150, 170 sothat the spinal implant 100 may have a variety of configurations.

The independent adjustability of the proximal and distal regions 100 a,100 b of the spinal implant 100 allows a clinician to adjust thedimensions of the spinal implant 100 (i.e., vertical heights of theproximal and distal regions) such that the spinal implant 100 can beinserted between two vertebrae with relatively narrow access in thecollapsed position, without force, to avoid trauma to the vertebralbodies, and in particular, the endplates of the vertebral bodies. Theproximal and/or distal regions 100 a, 100 b of the spinal implant 100can then be adjusted to partially or fully expanded positions so thatthe upper and lower bodies 110, 130 are aligned with the endplates tomaximize surface contact between the spinal implant 100 and theendplates, and to match the dimensions of the disc space defined betweenthe endplates in which the spinal implant 100 is disposed. Theadjustability of the spinal implant 100 allows a clinician, for example,to minimize trauma to the vertebrae during implantation of the spinalimplant 100, to tailor the spinal implant 100 to conform to the anatomyof individual patients, to maximize contact between the spinal implant100 and the endplates to create bone growth, to match the natural discheight of the disc space, to improve the seating of the spinal implant100 within the disc space, and/or to lessen the likelihood of expulsionof the spinal implant 100 from the disc space.

As shown in FIGS. 4A-4E, the spinal implant 100 has a collapsed, orunexpanded, position. In the collapsed position, planar portions 112,132 of the upper and lower bodies 110, 130 are disposed in parallelrelationship to each other. Each of the proximal and distal regions 100a, 100 b of the spinal implant 100 has a height, “h1,” that defines theminimum distance at which the upper and lower bodies 110, 130 may bepositioned relative to each other. In embodiments, height, “h1,” mayrange from about 2 mm to about 12 mm. The ramp 152 is disposed in aproximalmost position such that the first and second set of pins 151 and153 are engaged with the distalmost groove of the plurality of grooves169, and the curved plate 176 is disposed in a proximalmost positionwith the nubs 190 of the curved plate 176 disposed in a proximalmostpart of the longitudinal slots 188 a of the bracket 174 such that theupper and lower pivot linkages 178, 180 are in the collapsed position.

The ramp 152 of the proximal adjustment assembly 150 may be advanceddistally between the upper and lower bodies 110, 130 to drive the upperand lower bodies 110, 130 apart at the proximal region 100 a of thespinal implant 100. As shown in FIGS. 5A-5B, the ramp 152 may be moveddistally such that the first and second set of pins 151, 153 are movedto a groove in the plurality of grooves 169 adjacent to the distalmostgroove of the embodiment of FIGS. 4A-4E to partially expand the proximalregion 100 a of the spinal implant 100 to a height, “h2,” to provide thespinal implant 100 with a kyphotic shape. In embodiments, the height,“h2,” may range from about 3 mm to about 13 mm. In some embodiments,each groove 169 provides 1 mm of expansion at the proximal region 100 aof the spinal implant 100. However, it should be understood that thegrooves 169 may be configured to provide different amounts of expansionbased on the size and number of grooves provided in the upper and lowerrails 156, 158 of the ramp 152. For example, each groove 169 may providemore or less than 1 mm of expansion and the amount of expansion for eachgroove 169 may not be uniform along the upper and lower rails 156, 158.As shown in FIGS. 6A-6E, the ramp 152 may be fully advanced such thatthe first and second set of pins 151, 153 are moved into a proximalmostgroove of the plurality of grooves 169 to achieve maximum expansion atthe proximal region 100 a of the spinal implant 100. When fullyadvanced, the proximal wall 154 of the ramp 152 is flush with theproximal ends 112 a, 132 a of the upper and lower bodies 110, 130.

The distal adjustment assembly 170 can be actuated by driving thethreaded post 172 distally through the threaded openings 184 a, 182 a ofthe boss 174 and base plate 182 of the bracket 174 to push the curvedplate 176 against the upper and lower pivot linkages 178, 80 to move theupper and lower pivot linkages 178, 180 apart. Thus, movement of thecurved plate 176 controls the displacement of the upper and lower pivotlinkages 178, 180 relative to each other.

As shown in FIGS. 7A-7B, with the proximal region 100 a of the spinalimplant 100 in the partially expanded position of FIGS. 5A-5B, rotationof the threaded post 172 in a first direction moves the threaded post172 distally which in turn, pushes the curved plate 176 (see e.g., FIG.10E) distally such that the nubs 190 of the curved plate move distallywithin the longitudinal slots 188 a of the bracket 174 and the curveddistal surface 176 a of the curved plate 176 (FIG. 2) pushes against theupper and lower pivot linkages 178 and 180 to change the distancebetween the upper and lower bodies 110, 130 in the distal region 100 bof the spinal implant 100. The distal region 100 b of the spinal implant100 may be adjusted to have the same height, “h2,” as the proximalregion 100 a of the spinal implant 100 such that the upper and lowerbodies 110, 130 are parallel to each other. As shown in FIGS. 8A-8B,with the proximal region 100 a of the spinal implant in a partiallyexpanded position having a height, “h3,” the threaded post 172 may befully advanced such that the nubs 190 of the curved plate 176 aredisposed in a distalmost portion of the longitudinal slots 188 a of thebracket 174 to achieve maximum expansion at the distal region 100 b, toa height, “h4,” of the spinal implant 100. In embodiments, the height,“h3,” may range from about 3 mm to about 13 mm, and the height, “h4,”may range from about 8 mm to about 18 mm.

As shown in FIGS. 9A-9B, with the proximal region 100 a of the spinalimplant 100 in the fully expanded position, as previously illustrated inFIGS. 6A-6E, the threaded post 172 is moved a distance axially such thatthe distal region 100 b of the spinal implant 100 is adjusted to havethe same height as the proximal region 100 a of the spinal implant 100.As shown in FIGS. 10A-10E, the distal adjustment assembly 170 is shownin a fully expanded position to achieve maximum expansion of both theproximal and distal regions 100 a, 100 b of the spinal implant 100.

A person of ordinary skill in the art will readily understand that theproximal and distal regions of the spinal implant may be independentlyadjusted to achieve a desired configuration of the spinal implant.Accordingly, it is contemplated that only the proximal region or thedistal region of the spinal implant may be expanded, should that be adesired configuration, or both the proximal and distal regions of thespinal implant may be expanded to achieve a desired configuration (e.g.,an implant having a kyphotic shape, a lordotic shape, etc.).

Referring now to FIGS. 11A-11J, a method for inserting, positioning,and/or adjusting (e.g., expanding) the spinal implant 100 in aninterdisc space between adjacent vertebral bodies with an insertioninstrument 10 is shown. As shown in FIG. 11A, a tip 11 of the insertioninstrument 10 is aligned with the proximal region 100 a of the spinalimplant 100 disposed in the collapsed position. As shown in FIG. 11B,the tip 11 of the insertion instrument 10 is placed into the spinalimplant 100 through the central opening 154 a of the proximal wall 154of the ramp 152, between the upper and lower bodies 110 and 130 of thespinal implant 100, and over the boss 184 of the bracket 174 (see e.g.,FIG. 2). As shown in FIG. 11C, the insertion instrument 10 is rotated 90degrees so that the tip 11 engages the partially flanged proximal end184 b of the boss 184 (see e.g., FIG. 3D) for releasable attachment ofthe insertion instrument 10 to the spinal implant 100. As shown in FIGS.11D-11E, handles 12 of the insertion instrument 10 may be squeezedand/or a thumb wheel 13 of the insertion instrument 10 may be rotated toadvance the tip 11 of the insertion instrument 10 distally into the ramp152 such that a flanged portion 14 of the insertion instrument 10 abutsthe proximal wall 154 of the ramp 152 to push the ramp 152 between theupper and lower bodies 110 and 130 and thus, expand the proximal region100 a of the spinal implant 100 as shown in FIGS. 11F and 11G.

As shown in FIG. 11H, a driver 15 is inserted through the insertioninstrument 10 and includes a shaped distal end 16 configured to engagethe proximal end 172 b of the threaded post 172 (see e.g., FIG. 2) ofthe spinal implant 100. As shown in FIG. 11I, as the driver 15 isrotated, the threaded post 172 is also rotated and moved distallyagainst the curved plate 176 thereby moving the curved plate 176 intothe upper and lower pivot linkages 178 and 180 (see e.g., FIG. 2) toexpand the distal region 100 b of the spinal implant 100, as shown inFIG. 11J.

While shown fully expanded, it should be understood that the insertioninstrument 10 may be advanced and/or the driver 15 may be rotated toexpand the proximal and/or distal regions 100 a, 100 b of the spinalimplant 100 to any desired position.

In use, a clinician removes all or a portion of a disc from between twovertebral bodies (e.g., complete or partial diskectomy), and scrapes andcleans the endplates of the vertebral bodies to prepare the surfaces forplacement of the spinal implant 100 such that a fusion will occur. Next,the clinician places the spinal implant 100 into the disc space usingthe insertion instrument 10. The insertion instrument 10 is attached tothe implant by inserting the tip 11 of the insertion instrument 10 overthe boss 184 of the bracket 174 and rotating the insertion instrument 10ninety (90) degrees to engage the partially flanged proximal end 184 bof the boss 184, as described above. The insertion instrument 10 may bepre-attached to the spinal implant 100 prior to inserting the spinalimplant 100 into the disc space, or may be attached after the spinalimplant 100 is positioned in the disc space. The handles 12 and/or thethumb wheel 13 of the insertion instrument 10 is actuated to drive theramp 152 distally into the spinal implant 100 and thus increase theproximal height of the spinal implant 100 in discrete increments (e.g.,1 mm increments) as the first and second set of pins 151, 153 advancedistally into grooves 169 of the respective upper and lower rails 156,158. With the driver 15 inserted through the insertion instrument 10 toengage threaded post 172, rotation of the driver 15 in a first direction(e.g., clockwise) drives the threaded post 172 distally against thecurved plate 176 to expand the upper and lower pivot linkages 178, 180and thus, increase the distal height of the spinal implant 100.

Various allograft and/or autograft materials may be placed into and/ornext to the spinal implant 100 to assist in the fusion process. Shouldthe clinician need to adjust the distal height of the implant 100 onceit is expanded, the driver 15 would be re-engaged with the threaded post172 and rotated in a second direction (e.g., counter-clockwise) to drivethe threaded post 172 proximally. Should the proximal height need to beadjusted, a separate instrument (not shown) would be utilized to movethe upper and lower bodies 110 and 130 away from the ramp 152.

Referring now to FIGS. 12A and 12B, an expandable spinal implant orspinal implant 200 in accordance with another embodiment of the presentdisclosure is shown. The spinal implant 200 is similar to the spinalimplant 100 and therefore will be described with respect to thedifferences therebetween.

The spinal implant 200 has a proximal region 200 a and a distal region200 b, and includes an upper body 210 and a lower body 230 disposed inopposed relation relative to each other and coupled together by aproximal adjustment assembly 250 and a distal adjustment assembly 270.The proximal and distal adjustment assemblies 250 and 270 areindependently movable to allow for adjustment in the angular andvertical distance between the upper and lower bodies 210, 230 of theproximal and distal regions 200 a, 200 b of the spinal implant 200.

The independent adjustability of the proximal and distal regions 200 a,200 b of the spinal implant 200 allows a clinician to adjust thedimensions of the spinal implant 200 (i.e., vertical heights of theproximal and distal regions) such that the spinal implant 200 can beinserted between two vertebrae with relatively narrow access in thecollapsed position, without force, to avoid trauma to the vertebralbodies, and in particular, the endplates of the vertebral bodies. Theproximal and/or distal regions 200 a, 200 b of the spinal implant 200can then be adjusted to partially or fully expanded positions so thatthe upper and lower bodies 210, 230 are aligned with the endplates tomaximize surface contact between the spinal implant 200 and theendplates, and to match the dimensions of the disc space defined betweenthe endplates of the vertebral bodies in which the spinal implant 200 isdisposed. The adjustability of the spinal implant 200 allows aclinician, for example, to minimize trauma to the vertebrae duringimplantation of the spinal implant 200, to tailor the spinal implant 200to conform to the anatomy of individual patients, to maximize contactbetween the spinal implant 200 and the endplates to create bone growth,to match the natural disc height of the disc space, to improve theseating of the spinal implant 200 within the disc space, and/or tolessen the likelihood of expulsion of the spinal implant 200 from thedisc space.

Turning now to FIG. 13, the upper body 210 of the spinal implant 200includes an elongated substantially planar portion 212 and a curvedportion 214 disposed distally of the planar portion 212. An outersurface 216 of the planar portion 212 includes a plurality of retainingfeatures 216 a. An inner surface 218 of the upper body 210 includes apair of proximal fins 220 and a pair of distal posts 222. Each proximalfin 220 includes an angled slot 220 a and a vertical slot 220 b definedtherein. The angled slot 220 a is disposed proximal to the vertical slot220 b. Each distal post 222 includes a through hole 222 a definedtherethrough.

The lower body 230 includes an elongated substantially planar portion232 and a curved portion 234 disposed distally of the planar portion232. The planar portion 232 includes an outer surface 236 having aplurality of retaining features 236 a disposed thereon. An inner surface238 of the lower body 230 includes a pair of proximal fins 240 and apair of distal posts 242. Each proximal fin 240 includes an angled slot240 a and a vertical slot 240 b defined therein. Each distal post 242includes a through hole 242 a defined therethrough.

The proximal adjustment assembly 250 includes, a linkage body 252, aflange nut 254 disposed proximally of the linkage body 252, and acoupler 256 disposed distally of the linkage body 252. The linkage body252 includes a central opening 252 a defined therethrough, and a recess252 b defined in a proximal portion of the linkage body 252 between apair of arms 258 extending along lateral sides of the linkage body 252.The arms 258 include proximal holes 258 a that are dimensioned to engagean insertion instrument 20 (see e.g. FIG. 18A) and distal holes 258 bthat are aligned with the angled slots 220 a, 240 a of the proximal fins220, 240 of the upper and lower bodies 210, 230. A first set of pins 251respectively extends through and frictionally engages the distal hole258 b and the angled slots 220 a, 240 a of the proximal fins 220, 240 ofthe upper and lower bodies 210, 230 to adjustably couple the upper andlower bodies 210, 230 together via the linkage body 252. The first setof pins 251 is configured to ride along the angled slots 220 a, 240 a ofthe proximal fins 220, 240 of the upper and lower bodies 210, 230 as thelinkage body 252 is moved proximally and/or distally within the upperand lower bodies 210, 230.

The coupler 256 includes a central opening 256 a defined therein thathas the same size and shape as the central opening 252 a of the linkagebody 252. The central openings 252 a and 256 a of the linkage body 252and the coupler 256 are sized and shaped to engage, and be supported on,a shaft 282 of an expander 274 of the distal adjustment assembly 270.The coupler 256 also includes a pair of nubs 260 having flanged outerends 260 a extending laterally from sides thereof that are dimensionedto be retained and slide within the vertical slots 220 b, 240 b of theproximal fins 220, 240 of the upper and lower bodies 210, 230.

The flange nut 254 includes a body portion 254 a having a flanged distalend 254 b and a threaded opening 254 c defined therethrough that isconfigured to threadingly engage a threaded post 272 of the distaladjustment assembly 270 and be rotated and axially translated along thethreaded post 272. The flanged distal end 254 b of the flange nut 254 isdimensioned to be received within the recess 252 b of the linkage body252. Accordingly, movement of the flange nut 254 distally moves thelinkage body 252 distally causing the first set of pins 251 to translatewithin the angled slots 220 a, 240 a of the proximal fins 220, 240 andthe nubs 260 of the coupler 256 to translate within the vertical slots220 b, 240 b of the proximal fins 220, 240 to increase the distancebetween the upper and lower bodies 210 and 230 at the proximal region200 a of the spinal implant 200. Conversely, movement of the flange nut254 proximally moves the linkage body 252 proximally to reduce thedistance between the upper and lower bodies 210, 230 at the proximalregion 200 a of the spinal implant 200.

The distal adjustment assembly 270 includes a threaded post 272, anexpander 274, and a pivot linkage assembly 275 (see e.g., FIG. 15)including an upper pivot linkage 276 and a lower pivot linkage 278. Thethreaded post 272 includes an elongated threaded body 272 a having ahex-shaped proximal end 272 b (see e.g., FIG. 12B) configured to matewith a driver 23 of an insertion instrument 20 (see e.g., FIG. 18D) anda distal end 272 c. The expander 274 includes a body portion 280defining a cavity 280 a therein. A pair of opposed longitudinal slots280 b is disposed on lateral sides of the body portion 280, and a distalend of the body portion 280 includes a double ramped inner surface 280 c(see e.g., FIG. 14C). A shaft 282 extends proximally from the bodyportion 280 of the expander 274 and defines a threaded opening 282 atherethrough that is configured to receive the threaded post 272.

The pivot linkage assembly 275 includes an upper pivot linkage 276having an upper hole 276 a and a lower hole 276 b, and a lower pivotlinkage 278 having an upper hole 278 a and a lower hole 278 b. The upperhole 276 a of the upper pivot linkage 276 is aligned with the throughholes 222 a defined in the distal posts 222 of the upper body 210, and asecond set of pins 252 is inserted therethrough for pivotably connectingthe upper pivot linkage 276 with the upper body 210. The lower hole 278b of the lower pivot linkage 278 is aligned with the through holes 242 adefined in the distal posts 242 of the lower body 230, and a pin 255 isinserted therethrough for pivotably connecting the lower pivot linkage278 with the lower body 230. The lower hole 276 b of the upper pivotlinkage 276 and the upper hole 278 a of the lower pivot linkage 278 arealigned with each other and with the longitudinal slots 280 b defined inthe expander 274 such that the upper and lower pivot linkages 276 and278 are disposed within the cavity 280 a in the body portion 280 of theexpander 274, and a pin 257 is disposed therethrough for pivotablysecuring the upper and lower bodies 210 and 230 to the expander 274 ofthe distal adjustment assembly 270 via the upper and lower pivotlinkages 276, 278. This arrangement allows for simultaneous translationof the pin 257 within the longitudinal slots 280 b of the expander 274and pivoting movement of the upper and lower pivot linkages 276, 278.

In use, the threaded post 272 is rotated in a first direction to advancethe threaded post 272 distally until it pushes against and drives theupper and lower pivot linkages 276, 278 against the double ramped innersurface 280 c of the expander 274 thereby increasing the height betweenthe upper and lower bodies 210, 230 at the distal region 200 b of thespinal implant 200. Rotation of the threaded post 272 in a second,reverse direction moves the threaded post 272 proximally to allow theupper and lower pivot linkages 276, 278 to collapse, thereby decreasingthe height between the upper and lower bodies 210, 230 at the distalregion 200 b of the spinal implant 200.

As shown in FIGS. 14A-14C, the spinal implant 200 has a collapsed, orunexpanded, position. In the collapsed position, the planar portions212, 232 of the upper and lower bodies 210, 230 are disposed in parallelrelationship to each other. The first set of pins 251 of the linkagebody 252 and the nubs 260 of the coupler 256 are disposed within theangled slots 220 a, 240 a and the vertical slots 220 b, 240 b,respectively, of the proximal fins 220, 240 of the upper and lowerbodies 210, 230 such that the nubs 260 rest within an uppermost portionof the vertical slot 220 a of the upper body 210 and a lowermost portionof the vertical slot 240 b of the lower body 230. The pin 257 disposedthrough the expander 274 and the upper and lower pivot linkages 276, 278is disposed in a proximalmost position within the longitudinal slots 280b of the expander 274 so that the upper and lower pivot linkages 276,278 are in the collapsed position.

As shown in FIG. 15, rotation of the threaded post 272 in a firstdirection moves the threaded post 272 distally through the threadedopening 254 c of the flange nut 254 and the threaded opening 282 a ofthe shaft 282 of the expander 274 which, in turn, pushes the upper andlower pivot linkages 176, 178 into the double ramped inner surface 280 cof the expander 274 to change the distance between the upper and lowerbodies 210, 230 about the distal region 200 b of the spinal implant 200.Continued rotation of the threaded post 272 in the distal directioncauses the upper and lower pivot linkages 276, 278 to move into a fullyexpanded position, as shown in FIG. 16. In the fully expanded state, thepin 257 is disposed in a distalmost position within the longitudinalslot 280 b of the expander 274.

The flange nut 254 of the proximal adjustment assembly 250 may beadvanced distally between the upper and lower bodies 210, 230 to drivethe upper and lower bodies 210, 230 apart at the proximal region 200 aof the spinal implant 200, as shown in FIGS. 17A-17B. Rotation of theflange nut 254 in a first direction moves the flange nut 254 and thelinkage body 252 distally such that the first set of pins 251 slidewithin the angled slots 220 a, 240 a of the proximal fins 220, 240 ofthe upper and lower bodies 210 and 230, and the nubs 260 of the coupler256 slide within the vertical slots 220 b, 240 b to partially or fullyexpand the proximal region 200 a of the spinal implant 200. The proximalregion 200 a of the spinal implant 200 is fully expanded when the nubs260 of the coupler 256 are disposed within a lowermost portion of thevertical slot 220 a of the upper body 210 and an uppermost portion ofthe vertical slot 240 b of the lower body 230. While the distal region200 b of the spinal implant 200 is shown in the fully expanded positionof FIG. 16, it should be understood that the distal region 200 b mayhave any desired configuration.

Referring now to FIGS. 18A-18E, the spinal implant 200 and an insertioninstrument 20 are shown. As shown in FIG. 18A, the insertion instrument20 includes feet 21 disposed at a distal end thereof that are configuredto engage the proximal through holes 258 a of the linkage body 252 ofthe spinal implant 200. As shown in FIG. 18B, the insertion instrument20 includes hinges 22 that allow the feet 21 to flex for releasablepositioning of the feet 21 into the proximal through holes 258 a of thespinal implant 200. As shown in FIGS. 18C-18E, a driver 23 is insertedthrough an opening 20 a of the insertion instrument 20, and includes ashaped distal end 24, such as a hex portion, configured to make with thehex-shaped proximal end 272 b of the threaded post 272. A handle 25 ofthe driver 23 is rotated in a first or second direction to rotate thethreaded post 272 which, in turn, moves the threaded post 272 distallyor proximally to adjust the height of the distal region 200 b of thespinal implant 200. A thumb wheel 26 of the insertion instrument 20 isrotated in a first or second direction to rotate the flange nut 254which, in turn, moves the flange nut 254 distally or proximally toadjust the height of the proximal region 200 a of the spinal implant200.

In use, a clinician removes all or a portion of a disc from between twovertebral bodies (e.g., complete or partial diskectomy) and cleans theend plates of the vertebral bodies, as discussed above. The clinicianthen places the spinal implant 200 into the disc space using theinsertion instrument 20, and may adjust the height of the proximaland/or distal regions 200 a and 200 b of the spinal implant 200 asdescribed above. Various allograft and/or autograft materials may beused to assist in the fusion process.

Referring now to FIGS. 19 and 20, an expandable spinal implant or spinalimplant 300 in accordance with another embodiment of the presentdisclosure is shown. The spinal implant 300 is similar to spinalimplants 100 and 200, and thus will be described with respect to thedifferences therebetween.

The spinal implant 300 has a proximal region 300 a and a distal region300 b, and includes an upper body 310 and a lower body 330 disposed inopposed relation relative to each other and coupled together by aproximal adjustment assembly 350 and a distal adjustment assembly 370.The proximal and distal adjustment assemblies 350 and 370 areindependently movable to allow for adjustment in the angular andvertical distance between the upper and lower bodies 310 and 330 of theproximal and distal regions 300 a and 300 b of the spinal implant 300.

The independent adjustability of the proximal and distal regions 300 a,300 b of the spinal implant 300 allows a clinician to adjust thedimensions of the spinal implant 300 (i.e., vertical heights of theproximal and distal regions) such that the spinal implant 300 can beinserted between two vertebrae with relatively narrow access in thecollapsed position, without force, to avoid trauma to the vertebralbodies, and in particular, the endplates of the vertebral bodies. Theproximal and/or distal regions 300 a, 300 b of the spinal implant 300can then be adjusted to partially or fully expanded positions so thatthe upper and lower bodies 310, 330 are aligned with the endplates tomaximize surface contact between the spinal implant 300 and theendplates, and to match the dimensions of the disc space defined betweenthe endplates of the vertebral bodies in which the spinal implant 300 isdisposed. The adjustability of the spinal implant 300 allows aclinician, for example, to minimize trauma to the vertebrae duringimplantation of the spinal implant 300, to tailor the spinal implant 300to conform to the anatomy of individual patients, to maximize contactbetween the spinal implant 300 and the endplates to create bone growth,to match the natural disc height of the disc space, to improve theseating of the spinal implant 300 within the disc space, and/or tolessen the likelihood of expulsion of the spinal implant 300 from thedisc space.

Turning now to FIGS. 21, 22 a, and 22 b, the upper body 310 of thespinal implant 300 includes an elongated substantially planar portion312 and a curved portion 314 disposed distally of the planar portion312. The planar portion 312 is a two-piece construction including anouter surface 316 and a wing portion 318 disposed over the outer surface316. The outer surface 316 includes a plurality of retaining features316 a and a central recess 316 b including an opening 316 c definedtherein. The wing portion 318 includes an elongated body 318 a includingan outer surface 318 b including a plurality of retaining features 316a, and an inner surface 318 c including a flange (not shown) extendingtherefrom that is dimensioned to be received and retained within theopening 316 c of the outer surface 316 (e.g., the flange may be swagedor rolled into securement with upper body 310 to prevent separation ofthe wing portion 318 from the outer surface 316 of the upper body 310).

The wing portion 318 is movable from a first, retracted position inwhich the wing portion 318 is aligned with the outer surface 316 of theupper body 310 (see e.g., FIG. 19) and a second, deployed position inwhich the wing portion 318 is turned or rotated 90 degrees and disposedwithin the central recess 316 b defined in the outer surface 316 of theupper body 310 (see e.g., FIG. 20) such that the wing portion 318 isflush with the outer surface 316 to increase the surface area andfootprint of the outer surface 316 of the upper body 310. It should beunderstood that the planar portion 312 of the upper body 310 may be aone piece construction, as shown, for example in the embodiments ofspinal implants 100 and 200. Angled slots 320 a are disposed in aproximal portion of side surfaces 320 of the upper body 310, and ribfeatures 322 extends from the side surface 320 to strengthen the upperbody 310. An inner surface 324 of the upper body 310 includes a pair ofdistal posts 326 each including a through hole 326 a definedtherethrough.

The lower body 330 of the spinal implant 300 includes an elongatedsubstantially planar portion 332 and a curved portion 334 disposeddistal to the planar portion 332. The planar portion 332 is a two-piececonstruction including an outer surface 336 and a wing portion 338disposed over the outer surface 336. The outer surface 336 includes aplurality of retaining features 336 a and a central recess 336 bincluding an opening 336 c defined therein. The wing portion 338includes an elongated body 338 a including an outer surface 338 bincluding a plurality of retaining features 336 a, and an inner surface338 c including a flange 338 d extending therefrom that is dimensionedto be received within the opening 336 c of the outer surface 336, asdescribed above with respect to the wing portion 318 of the upper body310.

The wing portion 338 is movable from a first, retracted position inwhich the wing portion 338 is aligned with the outer surface 336 of thelower body 330 (see e.g., FIG. 19) and a second, deployed position inwhich the wing portion 338 is turned 90 degrees and disposed within thecentral recess 336 b defined in the outer surface 336 of the lower body330 (see e.g., FIG. 20) such that the wing portion 338 is flush with theouter surface 336 to increase the surface area and footprint of outersurface 336 of the lower body 330. It should be understood that theplanar portion 332 of the lower body 330 may be a one piececonstruction, as shown, for example in the embodiments of spinalimplants 100 and 200. An inner surface 340 of the lower body 330includes a pair of proximal fins 342 including angled slots 342 adefined therethrough, and a pair of distal posts 344 each including athrough hole 344 a defined therethrough. Rib features 346 extend fromlateral sides of the lower body 330 to strengthen the lower body 330.

Referring again to FIG. 21, the proximal adjustment assembly 350includes a plug 352, a nut 354 disposed distal to the plug 352, and abracket assembly 355 including first and second bracket bodies 356 a,356 b, and first and second bracket arms 358 a, 358 b. The plug 352includes a central opening 352 a defined therethrough that is configuredto engaged and slide relative to a shaft 382 of an expander 374 of thedistal adjustment assembly 370. The first bracket body 356 a has anL-shape and includes a plate 360 having an opening 360 a definedtherethrough, and an extension 362 extending proximally therefrom thatincludes an opening 362 a defined therethrough and a proximal nub 362 bextending from an inner surface 362 c of the extension 362. The secondbracket body 356 b also has an L-shape and includes a pair of spacedplates 364 having openings 364 a defined therethrough, and an extension366 extending proximally therefrom that includes an opening 366 adefined therethrough and a proximal nub 366 b extending from an innersurface 366 c of the extension 366. The plate 360 of the first bracketbody 356 a is received between the plates 364 of the second bracket body356 b such that the openings 360 a and 364 a are aligned and slidablyengaged with the shaft 382 of the expander 374 of the distal adjustmentassembly 370.

The first and second bracket arm 358 a, 358 b include outer surfaces 368each including a distal boss 368 a and a proximal nub 368 b. The distalbosses 368 a of the first and second bracket arms 358 a, 358 b aredimensioned to be received and retaining within the openings 362 a, 366a of respective extensions 362, 366 of the first and second bracketbodies 356 a, 356 b. The proximal nubs 368 a of the first and secondbracket arms 358 a and 358 b are dimensioned to be received and slidablyretained within the angled slots 320 a of the upper body 310, and theproximal nubs 362 b, 366 b of the extensions 362, 366 of the first andsecond bracket bodies 356 a, 356 b are dimensioned to be received andslidably retained within the angled slots 342 a defined in the proximalfins 342 of the lower body 330. Thus, the upper and lower bodies 310,330 are coupled together via the bracket assembly 355 of the proximaladjustment assembly 350.

The nut 354 includes a threaded opening 354 a that is configured tothreadingly engage a threaded post 372 of the distal adjustment assembly370, and be rotated and axially translated along the threaded post 372.Accordingly, distal movement of the nut 354 pushes and slides the plug352 and the bracket assembly 355 distally along the shaft 382 of theexpander 374 which, in turn, slides the proximal nubs 368 b disposedwithin the angled slots 320 a of the upper body 310, and the proximalnubs 362 b, 366 b disposed within the angled slots 342 a of the lowerbody 330, to increase the distance between the upper and lower bodies310 and 330 at the proximal region 300 a of the spinal implant 300.

The distal adjustment assembly 370 includes a threaded post 372, anexpander 374, and a pivot linkage assembly 375 (see e.g., FIG. 25C)including an upper pivot linkage 376 and a lower pivot linkage 378. Thethreaded post 372 includes an elongated threaded body 372 a having ashaped proximal end 372 b (see e.g., FIG. 26C) configured to mate withan insertion instrument (not shown) and a distal end 372 c. The expander374 includes a body portion 380 defining a cavity 380 a therein. A pairof opposed longitudinal slots 380 b are disposed on lateral sides of thebody portion 380, and a distal end of the body portion 380 includes adouble ramped inner surface 380 c (see e.g., FIG. 26C). A shaft 382extends proximally from the body portion 380 and defines a threadedopening 382 a therethrough that is configured to receive the threadedpost 372.

The pivot linkage assembly 375 includes an upper pivot linkage 376having an upper hole 376 a and a lower hole 376 b, and a lower pivotlinkage 378 having an upper hole 378 a and a lower hole 378 b. The upperhole 376 a of the upper pivot linkage 376 is aligned with the throughholes 326 a defined in the distal posts 326 of the upper body 310, and afirst set of pins 351 are inserted therethrough for pivotably connectingthe upper pivot linkage 376 with the upper body 310. The lower hole 378b of the lower pivot linkage 378 is aligned with the through holes 344 adefined in the distal posts 344 of the lower body 330, and a pin 353 isinserted therethrough for pivotably connecting the lower pivot linkage378 with the lower body 330. The lower hole 376 b of the upper pivotlinkage 376 and the upper hole 378 a of the lower pivot linkage 378 arealigned with the longitudinal slots 380 b defined in the expander 374such that the upper and lower pivot linkages 376 and 378 are disposedwithin the cavity 380 a in the body portion 380 of the expander 374, anda pin 357 is disposed therethrough for pivotably securing the upper andlower bodies 310 and 330 to the expander 374 of the distal adjustmentassembly 370 via the upper and lower pivot linkages 376 and 378.

In use, the threaded post 372 is advanced distally through the threadedopening 382 a of the shaft 382 of the expander 374, and into the cavity380 a defined in the body portion 380 of the expander 374 until itcontacts and pushes the upper and lower pivot linkages 376, 378 againstthe double ramped inner surface 380 c of the expander 374 therebyincreasing the height between the upper and lower bodies 310, 330 at thedistal region 300 b of the spinal implant 300. Movement of the threadedpost 372 in a reverse direction allows the upper and lower pivotlinkages 376, 378 to collapse, thereby decreasing the height between theupper and lower bodies 310, 330 at the distal region 300 b of the spinalimplant 300.

As shown in FIGS. 23A-24B, the spinal implant 300 has a collapsed, orunexpanded, position. In the collapsed position, the planar portions312, 332 of the upper and lower bodies 310, 330 are disposed in parallelrelationship to each other. Each of the proximal and distal regions 300a, 300 b of the spinal implant 300 has a height, “h5,” that defines theminimum distance at which the upper and lower bodies 310, 330 may bepositioned relative to each other, and each of the wing portions 318,338 has a height, “h6,” that defines the minimum distance at which thewing portions 318, 338 may be positioned relative to each other when inthe retracted position. In embodiments, the height, “h5,” may range fromabout 2.5 mm to about 12.5 mm, and the height, “h6,” may range fromabout 4 mm to about 14 mm. The proximal nubs 368 b of the bracket arms358 a, 358 b are disposed within an uppermost portion of the angledslots 320 a of the upper body 310 and the proximal nubs 362 b, 366 b ofthe bracket bodies 356 a, 356 b are disposed within a lowermost portionof the angled slots 342 a of the lower body 330. The pin 357 disposedthrough the expander 374 and the upper and lower pivot linkages 376 and378 is disposed in a proximalmost position within the longitudinal slots380 b of the expander 374 so that the upper and lower pivot linkages 376and 378 are in the collapsed position.

In the embodiment of FIGS. 23A and 23B, the wing portions 318, 338 ofthe upper and lower bodies 310, 330 are in the retracted position suchthat the spinal implant 300 has an unexpanded width, “w1,” and in theembodiment of FIGS. 24A and 24B, the wing portions 318, 338 of the upperand lower bodies 310, 330 are in the deployed position, such that thespinal implant 300 has an expanded width, “w2.” In embodiments, thewidth, “w1,” may range from about 9 mm to about 19 mm, and the width,“w2,” may range from about 22 mm to about 32 mm. Accordingly, in theretracted position, the spinal implant 300 has an increased overallheight and a decreased width compared to the deployed position.

The wing portions 318, 338 may be deployed independently or at the sametime and/or may be deployed at varying angles with respect to the upperand lower bodies 310 and 330. The wing portions 318, 338 are deployedmanually after insertion of the spinal implant 300 into a disc space,however, it is contemplated that the wing portions 318, 338 may bedeployed manually prior to insertion of the spinal implant 300 into thedisc space. The wing portions 318, 338 may be deployed with the use of atether or the like and then reversed back into alignment with the upperand lower bodies 310, 330.

As shown in FIG. 25A-25C, with the proximal region 300 a of the spinalimplant 300 in a collapsed position having a height, “h7,” rotation ofthe threaded post 372 in a first direction moves the threaded post 372distally and into contact with the upper and lower pivot linkages 376and 378 which, in turn, pushes the upper and lower pivot linkages 376and 378 into the double ramped inner surface 380 c (see e.g., FIG. 26C)of the expander 374 to change the distance between the upper and lowerbodies 310 and 330 about the distal region 300 b of the spinal implant300. Continued rotation of the threaded post 372 in the distal directioncauses the upper and lower pivot linkages 376 and 378 to move into afully expanded position in which the distal region 300 b has a height,“h8,” that forms an acute angle, “θ1,” with respect to a plane extendingalong the upper or lower body 310, 330. In embodiments, the height,“h7,” may range from about 2 mm to about 12 mm, the height, “h8,” mayrange from about 9 mm to about 19 mm, and the angle, “θ1,” may rangefrom about 8° to about 18°. In the fully expanded position, the pin 357is disposed in a distalmost position within the longitudinal slot 380 bof the expander 374.

As shown in FIGS. 26A-26C, the distal region 300 b of the spinal implant300 is shown in a partially expanded position due to rotation of thethreaded post 372, as described above. The proximal region 300 a of thespinal implant 300 is also partially expanded by rotating the nut 354distally along the threaded post 372 such that the nut 354 abuts theplug 352 and pushes the plug 352 into the bracket assembly 355 therebysliding the nubs 368 b in the angled slots 320 a of the upper body 310and the nubs 362 b and 366 b in the angled slots 342 a of the lower body330, causing the upper and lower bodies 310 and 330 to move apart aboutthe proximal region 330 a of the spinal implant 300. The proximal anddistal regions 300 a and 300 b are shown as having the same height,“h9.” In embodiments, the height, “h9,” may range from about 5.5 mm toabout 15.5 mm. It should be understood that the proximal and distalregions 300 a and 300 b may be adjusted alone or in combinations of thesame or different heights. As shown in FIGS. 27A-27C, the proximalregion 300 a of the spinal implant 300 is fully expanded to a height,“h10,” and the distal region 300 b of the spinal implant 300 is fullyexpanded to a height, “h11,” such that the spinal implant 300 has alordotic shape. In embodiments, the height, “h10,” may range from about5 mm to about 15 mm, and the height “h11,” may range from about 9 mm toabout 19 mm. The angle, “θ2,” defined at the distal region 300 b of thespinal implant 300 may range from about 1° to about 11°.

In use, a clinician remove all or a portion of the disc from between thetwo vertebral bodies (e.g., complete or partial diskectomy) and cleansthe endplates of the vertebral bodies, as discussed above. Next, theclinician places the implant 300 into the disc space using an insertioninstrument (not shown). Next, the wing portions may be deployeddepending on surgical need. Various allograft and/or autograft materialsmay be used to assist in the fusion process. Should the clinician needto adjust the height of the implant 300 after it is inserted between thevertebrae, the proximal and/or distal heights can be adjustedindependently, as discussed above with respect to spinal implants 100,200.

While embodiments shown and described herein illustrate exemplaryheights and/or widths of the spinal implant in collapsed, partiallyexpanded, and fully expanded positions, it should be understood thatother unexpanded and expanded heights and/or widths are alsocontemplated.

Persons skilled in the art will understand that the structures andmethods specifically described herein and shown in the accompanyingfigures are non-limiting exemplary embodiments, and that thedescription, disclosure, and figures should be construed merely asexemplary of particular embodiments. It is to be understood, therefore,that the present disclosure is not limited to the precise embodimentsdescribed, and that various other changes and modifications may beeffected by one skilled in the art without departing from the scope orspirit of the disclosure. Additionally, the elements and features shownand described in connection with certain embodiments may be combinedwith the elements and features of certain other embodiments withoutdeparting from the scope of the present disclosure, and that suchmodifications and variation are also included within the scope of thepresent disclosure. Accordingly, the subject matter of the presentdisclosure is not limited by what has been particularly shown anddescribed.

What is claimed is:
 1. A spinal implant having a proximal region and adistal region, the spinal implant comprising: an upper body including anouter surface and an inner surface; a lower body including an outersurface and an inner surface, the inner surfaces of the upper and lowerbodies disposed in opposed relation relative to each other; a proximaladjustment assembly disposed between the upper and lower bodies at theproximal region of the spinal implant and adjustably coupled to theupper and lower bodies; and a distal adjustment assembly disposedbetween the upper and lower bodies at the distal region of the spinalimplant and adjustably coupled to the upper and lower bodies, whereinthe proximal and distal adjustment assemblies are independently movableto change a vertical height of at least one of the proximal region orthe distal region of the spinal implant.
 2. The spinal implant accordingto claim 1, wherein the proximal adjustment assembly includes a rampslidably movable along the proximal region of the spinal implant tochange the vertical height of the proximal region of the spinal implant.3. The spinal implant according to claim 2, wherein the ramp includesupper and lower rails that taper from a proximal end towards a distalend of the ramp, and wherein the distal end of the ramp is disposedbetween the upper and lower bodies, and the ramp is slidable between theupper and lower bodies to increase the vertical height of the proximalregion of the spinal implant.
 4. The spinal implant according to claim3, wherein each of the upper and lower rails includes an inner surfacehaving a plurality of grooves extending along a length thereof, and theproximal adjustment assembly further includes: a first set of pinscoupled to the inner surface of the upper body and positioned againstthe inner surface of the upper rails; and a second set of pins coupledto the inner surface of the lower body and positioned against the innersurface of the lower rails, such the first and second sets of pins ridealong the plurality of grooves of the upper and lower rails duringmovement of the ramp.
 5. The spinal implant according to claim 1,wherein the distal adjustment assembly includes a pivot linkage assemblyincluding an upper pivot linkage pivotably connected to the innersurface of the upper body and a lower pivot linkage pivotably connectedto the inner surface of the lower body, the upper and lower pivotlinkages pivotably connected to each other and movable with respect toeach other to change the vertical height of the distal region of thespinal implant.
 6. The spinal implant according to claim 5, wherein thedistal adjustment assembly includes a curved plate having a curveddistal surface movable into and out of contact with the pivot linkageassembly to effect movement of the upper and lower pivot linkages withrespect to each other.
 7. The spinal implant according to claim 6,wherein the distal adjustment assembly includes a threaded postincluding a distal end retained against a proximal surface of the curvedplate, wherein axial movement of the threaded post moves the curvedplate.
 8. The spinal implant according to claim 7, wherein the distaladjustment assembly includes a bracket including a threaded opening anda pair of legs extending distally therefrom, wherein the threaded postis threadingly engaged with the threaded opening of the bracket and isaxially movable therethrough, and wherein the curved plate is slidablydisposed between the pair of legs of the bracket, and the upper andlower pivot linkages are pivotable connected to each other by a pinextending through the upper and lower pivot linkages and a distal end ofthe pair of legs of the bracket.
 9. The spinal implant according toclaim 5, wherein the distal adjustment assembly includes a threaded postincluding a distal end movable into and out of contact with the pivotlinkage assembly to effect movement of the upper and lower pivotlinkages with respect to each other.
 10. The spinal implant according toclaim 9, wherein the distal adjustment assembly includes an expanderincluding a body portion defining a cavity therein and a distal endincluding a double ramped inner surface, wherein the pivot linkageassembly extends through the cavity of the expander such that the upperand lower pivot linkages contact the double ramped inner surface of theexpander when moved by the threaded post.
 11. The spinal implantaccording to claim 10, wherein the expander includes a shaft extendingproximally from the body portion, the shaft including a threaded openingdefined therein, and wherein the threaded post is threadingly engagedwith the threaded opening of the shaft and axially movable therethroughinto the cavity of the expander.
 12. The spinal implant according toclaim 9, wherein each of the inner surfaces of the upper and lowerbodies includes a pair of proximal fins defining angled slotstherethrough, and wherein the proximal adjustment assembly includes: alinkage body including a pair of arms extending along lateral sidesthereof, each arm of the pair of arms including a distal hole; and afirst set of pins disposed within the distal holes of the linkage bodyand into the angled slots of the upper and lower bodies, such thatmovement of the linkage body causes the first set of pins to translatewithin the angled slots to change the vertical height of the proximalregion of the spinal implant.
 13. The spinal implant according to claim12, wherein the proximal adjustment assembly includes a flange nuthaving a threaded opening defined therethrough that is threadinglyengaged with the threaded post of the distal adjustment assembly, andthe linkage body includes a recess in which a distal flange of theflange nut is disposed, such that axial movement of the flange nut alongthe threaded post effects movement of the linkage body.
 14. The spinalimplant according to claim 13, wherein the pair of proximal fins of theupper and lower bodies defines vertical slots therethrough, and whereinthe proximal adjustment assembly includes a coupler that includes a pairof nubs extending from lateral sides thereof that is slidably disposedwithin the vertical slots of the upper and lower bodies.
 15. The spinalimplant according to claim 9, wherein side surfaces of the upper andlower bodies include angled slots defined therethrough, and wherein theproximal adjustment assembly includes a bracket assembly including aplurality of nubs slidably disposed within the angled slots of the upperand lower bodies, such that movement of the bracket assembly causes theplurality of nubs to translate within the angled slots to change thevertical height of the proximal region of the spinal implant.
 16. Thespinal implant according to claim 15, wherein the proximal adjustmentassembly includes a nut having a threaded opening defined therethroughthat is threadingly engaged with the threaded post of the distaladjustment assembly, such that axial movement of the nut along thethreaded post effects movement of the bracket assembly.
 17. The spinalimplant according to claim 1, wherein at least one of the outer surfacesof the upper and lower bodies includes a wing portion that is movablefrom a retracted position in which the wing portion is aligned with theouter surface of the upper body or the lower body, and a deployedposition in which the wing portion is rotated at an angle relative tothe outer surface of the upper body or the lower body.
 18. The spinalimplant according to claim 1, wherein at least one of the outer surfacesof the upper body or the lower body includes a plurality of retainingfeatures.
 19. A method of spacing vertebral bodies, comprising:implanting a spinal implant into a disc space defined between first andsecond endplates of respective first and second vertebral bodies suchthat an upper body of the spinal implant is adjacent the first end plateand a lower body of the spinal implant, disposed in opposed relationrelative to the upper body, is adjacent the second end plate, the spinalimplant including proximal and distal adjustment assemblies disposedbetween the upper and lower bodies, the proximal and distal adjustmentassemblies independently and adjustably coupled to proximal and distalregions, respectively, of the spinal implant; and adjusting a verticalheight of at least one of the proximal region or the distal region ofthe spinal implant via one of the proximal or distal adjustmentassemblies such that at least one of the outer surfaces of the upper orlower bodies of the spinal implant matches an anatomical shape of thefirst or second endplates of the first or second vertebral bodies.